Autoubiquitination
Autoubiquitination is the process by which a ubiquitin ligase (an E3 enzyme) attaches ubiquitin molecules to itself. This self-modification can regulate the ligase’s stability, activity, interactions, and subcellular localization, thereby influencing cellular signaling and protein turnover. Autoubiquitination occurs within the ubiquitin–proteasome system, following the general cascade in which ubiquitin is activated by E1, transferred to an E2, and then conjugated to a substrate by an E3 ligase; in autoubiquitination, the substrate is the E3 ligase itself.
The fate of autoubiquitination depends on the type of ubiquitin linkage. K48-linked chains commonly target the
Autoubiquitination is reversible by deubiquitinases, which can remove ubiquitin chains and restore ligase function. It serves
Autoubiquitination thus represents a key layer of control within the ubiquitin system, balancing protein turnover with